反应详情

2.4 g (0.0106 mol) of methyl 2-(2-hydroxyphenyl)-2-hydroxyimino-acetate (Example VII-1a from process step 3; HPLC: 17.1% E, log p=0.95; 68.9% Z, log p=1.68) in 60 ml of acetonitrile are heated under reflux with 1.08 g (0.011 mol) of potassiun bicarbonate and 1.55 g (0.0123 mol) of dimethyl sulphate for 10 hours. The reaction mixture is poured into water and extracted with diethyl ether, and the solvent is distilled off under reduced pressure. This gives 2.1 g of crude product which is chromatographed over silica gel using a mixture of 7 parts of n-hexane and 3 parts of acetone. This gives 1.6 g of product which, according to HPLC, contains 36.9% of methyl Z-2-(2-hydroxyphenyl)-2-methoxyimino-acetate of log p=2.39.

1. extractionextracted with diethyl ether
2. distillationthe solvent is distilled off under reduced pressure
3. customThis gives 2.1 g of crude product which is chromatographed over silica gel using
4. additiona mixture of 7 parts of n-hexane and 3 parts of acetone